During semiconductor manufacturing, a semiconductor wafer undergoes a plurality of process steps, each of which are performed by a specialized process tool. Pods are used to convey semiconductor wafers from one tool to another. Each pod is capable of transporting a number of wafers of a specific diameter. The pods are designed to maintain a protected internal environment to keep the wafers free of contamination, e.g., by particulates in the air outside the pod. Pods are also known for conveying other types of substrates, such as reticles, liquid crystal panels, rigid magnetic media for hard disk drives, solar cells, etc.
A loadport transfer device is defined to provide a standard mechanical interface to wafer fabrication production tools (process and/or metrology tools) to enable loading/unloading of pods into/out of wafer fabrication production tools, while ensuring protection of wafers therein from contamination. FIG. 1 shows an articulation schematic of a conventional loadport 10 having a window 12 through which a pod 14 is moved, in accordance with the prior art. The conventional loadport 10 is defined to move the pod 14 through the window 12 in a Y direction, and is defined to move the pod 14 in a Z direction. However, the conventional loadport 10 is not capable of moving the pod 14 in the X direction, i.e., in a horizontal direction. It is within this context that the present invention arises.